Yellowstone: World's First National Park

Yellowstone National Park was the first national park in the world, and larger than some U.S. states. And 90 percent of the park has barely been touched. And underneath Yellowstone, lies one of the world's largest volcanoes.

Yellowstone: World's First National Park

Yellowstone National Park was the first national park in the world, and larger than some U.S. states. And 90 percent of the park has barely been touched. And underneath Yellowstone, lies one of the world's largest volcanoes.